1. Technical Field
The present disclosure generally relates to backlight modules and, more particularly, to a backlight module with a heat dissipating member, and a liquid crystal display device incorporating the backlight module.
2. Description of Related Art
Recently, liquid crystal display devices have been in widespread use as display devices for compact electronic apparatuses. Typical liquid crystal display devices not only provide good quality images with little power consumption, but also are very thin. The liquid crystal in a liquid crystal display device does not emit any light itself. The liquid crystal has to be lighted by a light source so as to clearly and sharply display text and images. Thus, a backlight module is generally needed for a liquid crystal display device.
Referring to FIG. 1, a conventional backlight module 10 in a liquid crystal display device (not shown) includes a frame 11 and a bezel 12. The frame 11 is made of plastic material. The frame 11 includes two long side walls 111 and two short side walls 112. The bezel 12 is made of a metal piece. The bezel 12 includes a plate-shaped body 123, two long side plates 121 and two short side plates 122 extending from edges of the bezel 12. The long side walls 111 attach and cover the side plates 121 of the bezel 12. The side walls 111, 112 extend a plurality of catches (not labeled), and the side plates 121, 122 define a plurality of catch holes (not labeled) corresponding to the catches. Each of the catches of the side walls 111, 112 engages in a corresponding one of the catch holes of the side plates 121, 122, whereby the frame 11 and the bezel 12 are assembled together.
A part of heat generated by a light source in the backlight module 10 is absorbed by the bezel 12, and the other part of the heat is transferred by air flow inside the frame 11. Referring to FIG. 2, a heat path 21 of the conventional backlight module 10 is disclosed. Since the liquid crystal display device is vertically disposed for use, heated air in the backlight module 10 flows upwardly to top one of the long side walls 111. Nevertheless, the frame 11 is made of plastic material with low heat conductivity; thus, the heat is difficult to be transferred to ambient air via the side wall 111. The heated air accumulates in a top 23 of the backlight module 10 and slowly flows to the side walls 112 along a second heat path 22; it is difficult to transfer the heat to the ambient air. Thus, a heat dissipation efficiency of the liquid crystal display device is low. An accumulation of the heat may influence the performance and reliability of both the light source and electrical elements.
Another conventional backlight module includes a metallic frame and metallic bezel. The metallic frame is made of four metallic bars connecting to each other in series or integrally folded by a metallic plate. The metallic frame can quickly transfer heat generated in the backlight module to the ambient air. However, the metallic material of the frame makes the backlight module and the liquid crystal display device incorporating the backlight module somewhat costly and heavy.
What is needed, therefore, is a backlight module and a liquid crystal display device incorporating the backlight module which can overcome the above-described deficiencies.